Page 123 - Basics of MATLAB and Beyond

without specifying a property you get a list of all the allowed values
for every available property:

>> set(gca)
AmbientLightColor
Box: [ on | {off} ]
CameraPosition
CameraPositionMode: [ {auto} | manual ]
CameraTarget
CameraTargetMode: [ {auto} | manual ]
(and so on)

The properties for which you can choose values from among a short
list of alternatives will be shown. Other properties (for example, the
CameraPosition property above) can take on any numerical value, so a
list of alternatives is not shown. To get the format of such a property
(is the CameraPosition a scalar or a vector?) you can get its current
value:

>> get(gca,’CameraPosition’)
ans =
0.5000 0.5000 9.1603
Some properties are common to all objects. For example, all objects
have a “Type” property that specifies what kind of object it is (“Axes”,
“Figure”, “Patch” and so on), a “Parent” property (sometimes empty),
a “Visible” property that determines whether you can see it or not,
and a “Color” property (fairly obvious). Other properties are unique
to a particular kind of object. For example, only line objects have a
“LineWidth” property, and only “Figure” objects have an “InvertHard-
Copy” property.
Let us now consolidate these ideas with a few examples.

Example: Undo

When building a plot from the command line, it is good to have an
“oops” function that gets rid of the last thing you plotted. Let us start
2
by plotting a labelled parabola defined by f(x)= x .

x = -1:.01:1;
f = inline(’x.^2’);
clf
plt(x,f(x))

We use the text command to label the parabola.

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